The Aquaculture Stewardship Council is "sorry" that European retailers have decided to halt sales of pangasius and defended its environmental credentials.

Several supermarket chains in Europe, including Italy, Belgium, Spain, and France banned the sale of pangasius earlier this month, despite the EU insisting there were no health concerns with eating the fish.

European retailer Carrefour maintains that the quality of the fish is "impeccable", but that doubts remain over the environmental credentials of the farms in which they are raised.

The ASC said in a press release Wednesday that it "is sorry to see that a few retailers have decided to halt sales of pangasius." It said that when farmed according to ASC's pangasius standard, buyers and consumers "can have confidence" eating pangasius.

"Pangasius farms certified to the ASC standard can only be located in areas approved for aquaculture, and are required to measure various water parameters including nitrogen, phosphorus, and oxygen levels, at regular intervals to ensure they remain within set limits for optimal growing conditions.

"Strict procedures must also be followed to make sure that waste water does not pollute the ecosystem.

"Farms must also adhere to rigorous requirements to minimise disease outbreaks, must not use antibiotics unless truly necessary and then can only do so under the supervision of a veterinarian.

"As with all ASC standards, no antibiotics on the list of the World Health Organizations list of Critically Important Antimicrobials for human health can be used on a farm," it said.

"Because pangasius can be farmed efficiently, with low land use and limited use of feed, and can be produced in a way that respects the environment and communities, we feel there is space for the product in the competitive white fish market," it added.

ASC also noted that certification requires protections of workers' rights by insisting that all farms in the program offer employees contracts in keeping with International Labor Organization regulations.

"The ASC standard is frequently mentioned as the strongest certification on the market. We are dedicated to keeping it that way through consistent review in order to ensure that the standard reflects the best practices in aquaculture," it said.